<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Feed_Reader
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Rss.php 19044 2009-11-19 16:44:24Z padraic $
 */

/**
 * @see Zend_Feed_Reader_FeedAbstract
 */
require_once 'Zend/Feed/Reader/FeedAbstract.php';

/**
 * @see Zend_feed_Reader_Extension_Atom_Feed
 */
require_once 'Zend/Feed/Reader/Extension/Atom/Feed.php';

/**
 * @see Zend_Feed_Reader_Extension_DublinCore_Feed
 */
require_once 'Zend/Feed/Reader/Extension/DublinCore/Feed.php';

/**
 * @see Zend_Date
 */
require_once 'Zend/Date.php';

/**
 * @category   Zend
 * @package    Zend_Feed_Reader
 * @copyright  Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Feed_Reader_Feed_Rss extends Zend_Feed_Reader_FeedAbstract
{

	/**
	 * Constructor
	 *
	 * @param  DOMDocument $dom
	 * @param  string $type
	 */
	public function __construct(DomDocument $dom, $type = null)
	{
		parent::__construct($dom, $type);

		$dublinCoreClass = Zend_Feed_Reader::getPluginLoader()->getClassName('DublinCore_Feed');
		$this->_extensions['DublinCore_Feed'] = new $dublinCoreClass($dom, $this->_data['type'], $this->_xpath);
		$atomClass = Zend_Feed_Reader::getPluginLoader()->getClassName('Atom_Feed');
		$this->_extensions['Atom_Feed'] = new $atomClass($dom, $this->_data['type'], $this->_xpath);

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 && $this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$xpathPrefix = '/rss/channel';
		} else {
			$xpathPrefix = '/rdf:RDF/rss:channel';
		}
		foreach ($this->_extensions as $extension) {
			$extension->setXpathPrefix($xpathPrefix);
		}
	}

	/**
	 * Get a single author
	 *
	 * @param  int $index
	 * @return string|null
	 */
	public function getAuthor($index = 0)
	{
		$authors = $this->getAuthors();

		if (isset($authors[$index])) {
			return $authors[$index];
		}

		return null;
	}

	/**
	 * Get an array with feed authors
	 *
	 * @return array
	 */
	public function getAuthors()
	{
		if (array_key_exists('authors', $this->_data)) {
			return $this->_data['authors'];
		}

		$authors = array();

		if (empty($authors)) {
			$authors = $this->getExtension('DublinCore')->getAuthors();
		}

		if (empty($authors)) {
			if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 && $this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
				$list = $this->_xpath->query('//author');
			} else {
				$list = $this->_xpath->query('//rss:author');
			}

			foreach ($list as $authorObj) {
				$authors[] = $authorObj->nodeValue;
			}
		}

		if (empty($authors)) {
			$authors = $this->getExtension('Atom')->getAuthors();
		}

		if (empty($authors)) {
			$authors = null;
		} else {
			$authors = array_unique($authors);
		}

		$this->_data['authors'] = $authors;

		return $this->_data['authors'];
	}

	/**
	 * Get the copyright entry
	 *
	 * @return string|null
	 */
	public function getCopyright()
	{
		if (array_key_exists('copyright', $this->_data)) {
			return $this->_data['copyright'];
		}

		$copyright = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$copyright = $this->_xpath->evaluate('string(/rss/channel/copyright)');
		}

		if (!$copyright && !is_null($this->getExtension('DublinCore'))) {
			$copyright = $this->getExtension('DublinCore')->getCopyright();
		}

		if (empty($copyright)) {
			$copyright = $this->getExtension('Atom')->getCopyright();
		}

		if (!$copyright) {
			$copyright = null;
		}

		$this->_data['copyright'] = $copyright;

		return $this->_data['copyright'];
	}

	/**
	 * Get the feed creation date
	 *
	 * @return string|null
	 */
	public function getDateCreated()
	{
		return $this->getDateModified();
	}

	/**
	 * Get the feed modification date
	 *
	 * @return Zend_Date
	 */
	public function getDateModified()
	{
		if (array_key_exists('datemodified', $this->_data)) {
			return $this->_data['datemodified'];
		}

		$dateModified = null;
		$date = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$dateModified = $this->_xpath->evaluate('string(/rss/channel/pubDate)');
			if (!$dateModified) {
				$dateModified = $this->_xpath->evaluate('string(/rss/channel/lastBuildDate)');
			}
			if ($dateModified) {
				$dateStandards = array(Zend_Date::RSS, Zend_Date::RFC_822,
				Zend_Date::RFC_2822, Zend_Date::DATES);
				$date = new Zend_Date;
				foreach ($dateStandards as $standard) {
					try {
						$date->set($dateModified, $standard);
						break;
					} catch (Zend_Date_Exception $e) {
						if ($standard == Zend_Date::DATES) {
							require_once 'Zend/Feed/Exception.php';
							throw new Zend_Feed_Exception(
                                'Could not load date due to unrecognised'
                                .' format (should follow RFC 822 or 2822):'
                                . $e->getMessage()
                                );
						}
					}
				}
			}
		}

		if (!$date) {
			$date = $this->getExtension('DublinCore')->getDate();
		}

		if (!$date) {
			$date = $this->getExtension('Atom')->getDateModified();
		}

		if (!$date) {
			$date = null;
		}

		$this->_data['datemodified'] = $date;

		return $this->_data['datemodified'];
	}

	/**
	 * Get the feed description
	 *
	 * @return string|null
	 */
	public function getDescription()
	{
		if (array_key_exists('description', $this->_data)) {
			return $this->_data['description'];
		}

		$description = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$description = $this->_xpath->evaluate('string(/rss/channel/description)');
		} else {
			$description = $this->_xpath->evaluate('string(/rdf:RDF/rss:channel/rss:description)');
		}

		if (!$description && !is_null($this->getExtension('DublinCore'))) {
			$description = $this->getExtension('DublinCore')->getDescription();
		}

		if (empty($description)) {
			$description = $this->getExtension('Atom')->getDescription();
		}

		if (!$description) {
			$description = null;
		}

		$this->_data['description'] = $description;

		return $this->_data['description'];
	}

	/**
	 * Get the feed ID
	 *
	 * @return string|null
	 */
	public function getId()
	{
		if (array_key_exists('id', $this->_data)) {
			return $this->_data['id'];
		}

		$id = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$id = $this->_xpath->evaluate('string(/rss/channel/guid)');
		}

		if (!$id && !is_null($this->getExtension('DublinCore'))) {
			$id = $this->getExtension('DublinCore')->getId();
		}

		if (empty($id)) {
			$id = $this->getExtension('Atom')->getId();
		}

		if (!$id) {
			if ($this->getLink()) {
				$id = $this->getLink();
			} elseif ($this->getTitle()) {
				$id = $this->getTitle();
			} else {
				$id = null;
			}
		}

		$this->_data['id'] = $id;

		return $this->_data['id'];
	}

	/**
	 * Get the feed language
	 *
	 * @return string|null
	 */
	public function getLanguage()
	{
		if (array_key_exists('language', $this->_data)) {
			return $this->_data['language'];
		}

		$language = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$language = $this->_xpath->evaluate('string(/rss/channel/language)');
		}

		if (!$language && !is_null($this->getExtension('DublinCore'))) {
			$language = $this->getExtension('DublinCore')->getLanguage();
		}

		if (empty($language)) {
			$language = $this->getExtension('Atom')->getLanguage();
		}

		if (!$language) {
			$language = $this->_xpath->evaluate('string(//@xml:lang[1])');
		}

		if (!$language) {
			$language = null;
		}

		$this->_data['language'] = $language;

		return $this->_data['language'];
	}

	/**
	 * Get a link to the feed
	 *
	 * @return string|null
	 */
	public function getLink()
	{
		if (array_key_exists('link', $this->_data)) {
			return $this->_data['link'];
		}

		$link = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$link = $this->_xpath->evaluate('string(/rss/channel/link)');
		} else {
			$link = $this->_xpath->evaluate('string(/rdf:RDF/rss:channel/rss:link)');
		}

		if (empty($link)) {
			$link = $this->getExtension('Atom')->getLink();
		}

		if (!$link) {
			$link = null;
		}

		$this->_data['link'] = $link;

		return $this->_data['link'];
	}

	/**
	 * Get a link to the feed XML
	 *
	 * @return string|null
	 */
	public function getFeedLink()
	{
		if (array_key_exists('feedlink', $this->_data)) {
			return $this->_data['feedlink'];
		}

		$link = null;

		$link = $this->getExtension('Atom')->getFeedLink();

		if (!$link) {
			$link = null;
		}

		$this->_data['feedlink'] = $link;

		return $this->_data['feedlink'];
	}

	/**
	 * Get the feed generator entry
	 *
	 * @return string|null
	 */
	public function getGenerator()
	{
		if (array_key_exists('generator', $this->_data)) {
			return $this->_data['generator'];
		}

		$generator = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$generator = $this->_xpath->evaluate('string(/rss/channel/generator)');
		}

		if (!$generator) {
			if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
			$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
				$generator = $this->_xpath->evaluate('string(/rss/channel/atom:generator)');
			} else {
				$generator = $this->_xpath->evaluate('string(/rdf:RDF/rss:channel/atom:generator)');
			}
			if ($generator) {
				$generator = html_entity_decode($generator, ENT_QUOTES, $this->getEncoding());
			}
		}

		if (empty($generator)) {
			$generator = $this->getExtension('Atom')->getGenerator();
		}

		if (!$generator) {
			$generator = null;
		}

		$this->_data['generator'] = $generator;

		return $this->_data['generator'];
	}

	/**
	 * Get the feed title
	 *
	 * @return string|null
	 */
	public function getTitle()
	{
		if (array_key_exists('title', $this->_data)) {
			return $this->_data['title'];
		}

		$title = null;

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 &&
		$this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$title = $this->_xpath->evaluate('string(/rss/channel/title)');
		} else {
			$title = $this->_xpath->evaluate('string(/rdf:RDF/rss:channel/rss:title)');
		}

		if (!$title && !is_null($this->getExtension('DublinCore'))) {
			$title = $this->getExtension('DublinCore')->getTitle();
		}

		if (!$title) {
			$title = $this->getExtension('Atom')->getTitle();
		}

		if (!$title) {
			$title = null;
		}

		$this->_data['title'] = $title;

		return $this->_data['title'];
	}

	/**
	 * Read all entries to the internal entries array
	 *
	 */
	protected function _indexEntries()
	{
		$entries = array();

		if ($this->getType() !== Zend_Feed_Reader::TYPE_RSS_10 && $this->getType() !== Zend_Feed_Reader::TYPE_RSS_090) {
			$entries = $this->_xpath->evaluate('//item');
		} else {
			$entries = $this->_xpath->evaluate('//rss:item');
		}

		foreach($entries as $index=>$entry) {
			$this->_entries[$index] = $entry;
		}
	}

	/**
	 * Register the default namespaces for the current feed format
	 *
	 */
	protected function _registerNamespaces()
	{
		switch ($this->_data['type']) {
			case Zend_Feed_Reader::TYPE_RSS_10:
				$this->_xpath->registerNamespace('rdf', Zend_Feed_Reader::NAMESPACE_RDF);
				$this->_xpath->registerNamespace('rss', Zend_Feed_Reader::NAMESPACE_RSS_10);
				break;

			case Zend_Feed_Reader::TYPE_RSS_090:
				$this->_xpath->registerNamespace('rdf', Zend_Feed_Reader::NAMESPACE_RDF);
				$this->_xpath->registerNamespace('rss', Zend_Feed_Reader::NAMESPACE_RSS_090);
				break;
		}
	}
}
